Saturday, June 13, 2015

Mentioning institute affiliations is not enough - II

It has been said that man is a rational animal. All my life I have been searching for evidence which could support this - Bertrand Russell

In his post, Sanjeev says, 'Anything that is not measurable under their telescope or microscope or meters etc does not exist for them.' One reason for relying on instruments is that they are free of human biases. Perhaps the most problematic of these biases is confirmation bias - the tendency of people to look for evidence that confirms what they already believe. As Richard Feynman said, ' The first principle is that you must not fool yourself and you are the easiest person to fool.' Eyewitness testimony is a very unreliable form of evidence. People see what is not there and don't see what is there. Optical illusions show that people can be fooled by simple lines drawn on paper.

Instruments increase the range of signals that can be detected. For eg., the human eye can detect signals only in a narrow band of the electromagnetic spectrum and has limited power. Telescopes and microscopes enable us to see objects that are far away and tiny objects respectively, objects that can't be seen by human eyes. For eg., the Hubble Deep Field image is produced by pointing Hubble space telescope at an apparently empty patch of sky.It is revealed to contain many galaxies each with millions of stars many of which are a few billion times dimmer than what can be seen by the human eye.

Dogs can smell far better than humans, bats can hear sonar, insects an see in infra -red, birds can see in ultra-violet. Then there are signals like the magnetic field of the earth that you will not detect without instruments. Relying exclusively on human senses reveals a small world enabling humans to harbour the delusion that they are the pinnacle of creation. The vastly bigger universe revealed by instruments is far grander than the tiny universe revealed by human senses.Maybe everything we know about the universe now is wrong but what will replace it will be backed by evidence not dreams.

Sanjeev says, 'They do not have any conclusive logic to justify how they are so certain that no world apart from what can be measured by their scopes and meters can at all exist.' The conclusive logic is the absence so far of evidence to that effect. The personal experiences that people relate are very real and convincing to them but as evidence, they are worthless. As Oliver Sacks shows in his book Hallucinations(I had written a post about it), people can experience many things in many circumstances and be certain that they are real.

Sanjeev asks, “Who guided atoms to become humans?” Nobody. That was the brilliant discovery by Darwin. He noticed how breeders moulded the shapes and qualities of plants and animals in the way they wanted by choosing the breeding individuals in each generation. The entire first chapter of On the Origin of Species is devoted to artificial selection. But in artificial selection human beings are the controlling agents.

Then Darwin had his leap of imagination - why can't the same thing occur in nature with gradual change in wild plants and animals over many generations without the aid of a controlling agent? The individuals that breed in each generation are chosen automatically - those individuals that have the superior equipment to survive in their environment are most likely to reproduce and pass on the genes (a word that Darwin didn't use since he didn't know about them) that helped them to survive.

Sanjeev asks, “Why not slightest of evolution take place in documented history?”. If he means visible human evolution, then the time period is too small. Evolution by natural selection depends on the generation time of the organism and not enough human generations have gone by in recorded history for there to be visible evolutionary change. In organisms with shorter generation times, evolution has been documented. One of the most potent examples of evolution by natural selection which has the potential to cause havoc for humans in the not too distant future is the development of antibiotic resistance by bacteria.

Evolution by natural selection has occurred at the genetic level in human beings in recent times. An oft-cited example is the evolution of lactose tolerance in adults in pastoral communities. Another common example is the evolution of genetic resistance to malaria in some African populations due to hetero zygote advantage - When carrying two copies of an allele is disadvantageous (in this case, causing sickle-cell anaemia), but carrying only one copy is advantageous(in this case, conferring resistance to malaria). Isaac Asimov writes in his essay The Relativity of Wrong:

If the rate of change were more rapid, geology and evolution would have reached their modern state in ancient times. It is only because the difference between the rate of change in a static universe and the rate of change in an evolutionary one is that between zero and very nearly zero that the creationists can continue propagating their folly.

Actually, the idea of vast stretches of time should not faze the Indian mind since such ideas are part of myths.For eg., in Hindu mythology, there are 4 yugas which make up a cycle called divya-yuga, which lasts 4,320,000 years. One thousand of these yugas equal one day of Brahma. Brahma's lifespan is 100 years of this time. The idea of a 6000 years old earth believed by Young Earth Creationists in the US will strike the Indian mind as strange.

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About Me

I am an Engineer/MBA forced into early retirement. In 1999, at the age of 32, I suffered a brain stem stroke which left me a quadriplegic without speech. This blog is mainly about my life after the stroke.